Dry eye, including keratoconjunctivitis sicca, is a common ocular condition that can require therapy. Dry eye has been experienced by a broad demographic band, and is common in elderly individuals. A variety of current treatment modalities target physiological conditions that contribute to dry eye, including augmentation of normal tear fluid, enhancement of tear film component production, and methods to enhance the residence time of tears, such as blocking the tear flow from an eye into and through a lacrimal canaliculus.
Many current tear flow blockage techniques have drawbacks, including being irreversible in nature. For instance, some tear flow blockage techniques involve closing a canalicular canal by stitching the associated punctal opening shut or by using electrical or laser cauterization to seal the punctal opening. Although such procedures can provide the desired result of blocking tear flow to treat dry eye, they are not reversible without reconstructive surgery.
In addition to dry eye symptom relief, a variety of challenges face patients and physicians in the area of ocular, respiration and inner ear disease or disorder management, including adequate drug or other therapeutic agent delivery to the eyes, nasal passage or inner ear. In ocular management, for example, many current ocular drug delivery systems require repetitive manual administration and are often ineffective due to a lack of patient compliance or inadequate drug concentrations reaching the eye. For instance, when an eye drop is instilled in an eye, it often overfills the conjunctival sac (i.e., the pocket between the eye and the lids) causing a substantial portion of the drop to be lost due to overflow of the lid margin and spillage onto the cheek. A large portion of the drop remaining on the ocular surface can be washed away into and through a lacrimal canaliculus shortly after application, thereby diluting the concentration of the drug before it can absorbingly treat the eye. Moreover, topically applied drugs often have a peak ocular effect for about two hours post-application, after which additional applications of the drugs should be, but are often not, administered to maintain the desired drug therapeutic benefit.
In a field different from ocular management, control of respiration-related (e.g., allergies) and inner ear diseases or disorders often requires repetitive manual digestion or other intake of a medication (e.g., drugs or other therapeutic agents), and can be ineffective due to a lack of patient compliance or non-localized drug delivery.